Abstract:

Colloidal gold immunochromatographic assay was chosen to simultaneously detect five typical Salmonella
(Salmonella paratyphi A, Salmonella typhimurium, Salmonella choleraesuis, Salmonella enteritidis and Salmonella
anatum) in foods. In this assay, anti-Salmonella monoclonal antibody was labeled with colloidal gold while anti-Salmonella
monoclonal antibody and donkey anti-mouse IgG were dispensed onto nitrocellulose membrane as the test line and the
control line, respectively. The sensitivity of the developed strip to Salmonella paratyphi A was 105 CFU/mL and to the other
four strains was 106 CFU/mL. When food samples (e.g., milk and egg) were inoculated with 10–100 CFU Salmonella and
cultured for 16–20 h, positive results appeared on the test line of the strip. The developed method is rapid, efficient, sensitive
and specific. Therefore, it provides a valuable tool for simultaneously detecting different Salmonella species.

Key words: Salmonella, colloidal glod immunochromatographic assay, detection, food samples